Display device having resin black matrix over counter substrate

ABSTRACT

A display device is disclosed. The display device has a first substrate having a thin film transistor connected to a pixel electrode. Further, the display device has a second substrate opposed to the first substrate and having a resin black matrix.

This is a continuation of U.S. application Ser. No. 08/728,406, filedOct. 9, 1996, now U.S. Pat. No. 6,175,395.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an active matrix liquid crystal displaydevice.

2. Description of Related Art

Active matrix liquid crystal display devices are known as beingeffective for high-quality display. They are constructed such thatthin-film transistors are formed on a transparent substrate (usually aglass or quartz substrate) for respective pixels. Each thin-filmtransistor controls charge that enters or exits from an electrode (pixelelectrode) of the associated pixel. The active matrix liquid crystaldisplay devices require circuits (peripheral circuits) for driving thethin-film transistors for the respective pixels. In general, theperipheral circuits are constructed as an external IC circuit called adriver IC.

In an advanced version, the peripheral circuits formed by usingthin-film transistors are integrated on the substrate. Providing aunified structure in which the pixel region and the peripheral circuitregions are integrated on the same substrate, this configurationfacilitates the use of a liquid crystal panel.

As an example of application of the above liquid crystal panel, aprojection-type liquid crystal display apparatus will be describedbelow.

A first method of performing color display is to form color filters of R(red), G (green), and B (blue) in a liquid crystal panel. A secondmethod is to prepare a plurality of panels and combine images formed bythose panels. In recent years, with an increasing need for large screendisplay, the second method is used more frequently to implement aprojection-type display apparatus, because in the first method thesubstrate size needs to be increased and hence it is difficult tomanufacture a panel. The second method is disclosed in Japanese UtilityModel Laid-Open No. 58-111580.

In the second method, to combine images, the consistency of optical axesis important. Conventionally, liquid crystal panels are arrangedindependently and the modulating of optical axes is performed byadjusting the position and orientation of each panel in a subtle manner.However, this is not preferable because it causes a cost increase andcomplicates the structure of the apparatus. There is known a furthertechnique in which the same images are superimposed on each other toincrease the screen size or the brightness. However, this technique hasa problem of cost increase because it complicates the apparatusstructure.

To solve the above problems, attempts have been made to integrate thethree panels into a single panel. In this case, it is basicallysufficient to generate a set of images corresponding to three colors ofR, G and B. The brightness can be increased by generating two or moresets of images corresponding to R, G and B.

In this type of configuration, in forming peripheral driver circuitregions, it has been attempted to locate peripheral circuits that shouldbe integrated at a high density at positions as close to the center of asubstrate as possible, to increase a final production yield.

However, the above conventional liquid crystal display devices have twoproblems described below.

The first problem is as follows. A black matrix which is made of areflective metal such as Cr and occupies a large area of a displayscreen is formed on the inside surface of a upper transparent glasssubstrate that is located on the display screen side. External light isreflected by the black matrix and comes out of the display screen. Thislowers the contrast of a displayed image and hence makes it lessvisible, that is, lowers the display quality.

The second problem relates to a case where a black matrix is formed onan opposed substrate. In this case, as shown in FIG. 11A, a black matrix1 is so formed as to overlap with ITO pixel electrodes 2 by 5-7 μm inconsideration of the bonding accuracy of the TFT substrate and theopposed substrate. Thus, the size of opening portions is restricted. Inthis case, to increase the brightness of the display device, it isnecessary to employ a brighter back light, resulting in an increase inpower consumption.

FIG. 11A shows how the black matrix 1 on the opposed substrate and theITO pixel electrodes 2 overlap with each other. Reference numerals 3-5denote a signal line, a TFT, and a scanning line, respectively.

SUMMARY OF THE INVENTION

To solve the above two problems, an object of the present invention isto form a black matrix on TFTs of a driver circuit. This configurationhas an advantage that the overlapping width can be reduced to about 2 μmbecause of improved bonding accuracy that is obtained by forming theblack matrix and the ITO pixel electrodes on the same substrate.

This advantage will be described with reference to 11B. FIG. 11B showshow they overlap with each other in a case where the black matrix 1 isformed on the TFT substrate. While in the former case (FIG. 11A) theaperture ratio is about 15% (overlapping width: 7 μm), in the lattercase (FIG. 11B) it is greatly increased to about 40% (overlapping width:2 μm).

On the other hand, in the above-mentioned configuration in which theopposed substrate is made large enough to be opposed to the drivercircuits and the driver circuits are provided in the liquid crystalregion, the driver circuit regions and the pixel region come close toeach other, which requires light shielding even in the driver circuitregions.

Where the black matrix for light shielding of the pixel region is formedon the substrate on which TFTs are formed and is also used for lightshielding of the driver circuits to satisfy the above requirement, therehas occurred a problem that the capacitance of an interlayer insulatingfilm between TFTs of the driver circuits and the black matrix is notnegligible though the shielding itself does not cause any problem.

If the interlayer insulating film is a 3,000-Å-thick silicon nitridefilm, it has a unit area capacitance of 2.50×10⁻¹⁶ F/μm². For example,if a clock line or the like of a driver circuit has a wiring line of 100m in width and 50,000 μm in length, a capacitance formed by this wiringline of the driver circuit and the black matrix amounts to 1.25×10⁻⁹ F.In this case, if it is assumed that the wiring line of the drivercircuit has a sheet resistance of 0.2 Ω/μm², its delay time amounts to1.25×10⁻⁷ sec, which will cause a problem when the wiring line is drivenat several megahertz. The circuit characteristics are more important inthe driver circuits than in the pixel TFTs. Therefore, it is necessaryto reduce the capacitance of the interlayer insulating film formedbetween TFTs of the driver circuits and the black matrix.

It is practiced to form only a black matrix 16 for a pixel region 14 ona TFT substrate 11 so as to be adjacent to ITO electrodes 17 and form ablack matrix 18 for driver circuit regions 13 on an opposed substrate12, as shown in FIG. 12. However, although this configuration increasesthe aperture ratio, the number of manufacturing steps increases becauseof the need of forming the black matrix 16 and 18 on both of the TFTsubstrate 11 and the opposed substrate 12. In FIG. 12, referencenumerals 15 and 19 respectively denote an aluminum wiring line and colorfilters of R, G and B.

It is now desired to provide a liquid crystal display device whichenables light shielding of driver circuit regions without increasing thenumber of manufacturing steps.

Another object of the invention is to prevent a capacitance fromoccurring in an interlayer insulating film formed between TFTs of adriver circuit and a black matrix, to reduce, in turn, the delay time ofthe driver circuit, to thereby produce high-resolution images.

To attain the above objects, according to the invention, there isprovided an active matrix liquid crystal display device comprising: afirst insulating substrate comprising: a pixel region in which aplurality of pixels having respective thin-film transistors are arrangedin matrix form; a driver circuit region for driving the pixel region,the driver circuit region being provided on the same surface as thepixel region and having thin-film transistors; and a black matrix formedover the driver circuit region; a second insulating substrate opposed tothe first insulating substrate; and a liquid crystal material interposedbetween the first and second insulating substrates.

There is also provided an active matrix liquid crystal display devicecomprising: a first insulating substrate comprising: a pixel region inwhich a plurality of pixels having respective thin-film transistors arearranged in matrix form and a planation film is formed; a driver circuitregion for driving the pixel region, the driver circuit region beingprovided on the same surface as the pixel region and having thin-filmtransistors; and a black matrix formed over the first insulatingsubstrate a second insulating substrate opposed to the first insulatingsubstrate: and a liquid crystal material interposed between the firstand second insulating substrates.

Further, there is provided a liquid crystal display device comprising: apair of transparent substrates; a liquid crystal interposed between thepair of transparent substrates; 2n liquid crystal panels that areconstituted by using the pair of transparent substrates, where n is anatural number, the 2n liquid crystal panels comprising: active matrixpixel regions; driver circuits arranged around the pixel regions; and ablack matrix formed over the first insulating substrate; and means forcombining images produced by the 2n liquid crystal panels.

Still further, there is provided a liquid crystal display devicecomprising: a pair of transparent substrates; a liquid crystalinterposed between the pair of transparent substrates; 2n liquid crystalpanels that are constituted by using the pair of transparent substrates,where n is a natural number, the 2n liquid crystal panels comprising:active matrix pixel regions each having a planation film; drivercircuits arranged around the pixel regions, one side of each of thedriver circuits being adjacent to one of the pixel regions, and theother side being adjacent to the other pixel regions or the other drivercircuits; and a black matrix formed over the first insulating substrate;and means for combining images produced by the 2n liquid crystal panels.

In the invention, the insulating substrate means a substrate made of atransparent material that has a certain level of strength with respectto external force, for instance, an inorganic material such as glass orquartz.

Where thin-film transistors (hereinafter called TFTs) are formed on asubstrate, it is preferred to use a no-alkali glass substrate or aquartz substrate. Where it is intended to reduce the weight of a liquidcrystal panel, there may be used a film that is low in birefringence,such as PES (polyethylene sulfate).

A TFT that is formed for each pixel or a peripheral driver circuit maybe of a type in which the active layer is made of amorphous silicon orpolysilicon.

An ITO (alloy of indium oxide and tin) transparent electrodes are formedon a substrate as electrodes for driving a liquid crystal material. Inview of the heat resistance, it is desired to form a black matrix afterformation of the ITO electrodes.

To prevent contrast reduction due to irregular reflection within theliquid crystal display device, the black matrix used in the inventionmay be of a type in which a black material is dispersed in a transparentmaterial. Examples of the transparent material are inorganic materialssuch as glass and quartz and organic materials such as resin. From theviewpoint of easiness of manufacture, resin materials such as acrylicmaterials are preferred.

Examples of the black material are carbon black and a pigment. Forexamples, there may be used organic pigments of phthalocyanine pigments,quinacridon pigments, isoindolinone pigments, azo pigments,anthraquinone pigments, and dioxazine pigments.

Another method of forming the black matrix is to photosensitize anatural polymeric material such as gelatin, or a synthetic polymericmaterial such as polyvinyl alcohol, or polyvinyl pyrrolidone acrylicresin by a bichromate, then form a fine pattern by a photolithographicprocess, and finally dye it with an acid dye or a reactive dye.

A further method is to disperse a pigment such as carbon in aphotosensitive resin such as a PVA resin, an acrylic resin, or apolyimide resin, and then form a fine pattern by a photolithographicprocess.

Among the above processes, the method of dispersing carbon black in anacrylic resin is preferred because it can reduce the resistance and forma thin film.

The method of dispersing a black material in a resin material may beselected properly in accordance with the black material used, from astirring method using a stirrer, a ball mill method, three-roll allmethod, etc. The dispersiveness of the black material can be improved byadding a small amount of dispersing agent such as a surfactant during adispersing operation. To stabilize the dispersion and form a thin blackmatrix layer, it is desired that the average particle diameter of theblack material be about 0.1 μm. If the average particle diameter islarger than this value, there may occur color unevenness and hence theblack matrix does not accomplish the intended function.

A black matrix can be formed on a TFT substrate in a manner similar tothe manner of forming a resist pattern by an ordinary photolithographicmethod. That is, an organic solution in which a black material isdispersed is applied to a TFT substrate by spin coating or printing,then patterned by a known photographic method, and finally subjected topost-baking of about 200° C.

The second insulating substrate that is opposed to the substrate onwhich TFTs are formed made of the same material as the latter. Inaddition to a transparent electrode, a member such as color filters, ablack matrix, and/or a planation film may be formed on the opposedsubstrate when necessary. Where color filters are formed, first a blackmatrix is formed on the substrate, then color filters are formed, aplanation film is then formed to flatten the uneven surface, and finallya transparent electrode layer is formed.

The liquid crystal material may be a nematic, cholesteric, or smecticmaterial, or a dispersive liquid crystal in which one of those materialsis dispersed in a transparent resin material. In particular, because thedispersive liquid crystal does not require the use of a polarizingplate, it can provide a bright panel.

Where a nematic, cholesteric, or smectic liquid crystal material isused, an orientation treatment is performed on one or both of theopposed surface of the pair of substrates to orient the liquid crystalmaterial in a certain direction. The orientation treatment is actually arubbing treatment in which the substrate surface is rubbed with a clothor the like directly or through a thin film of an organic or inorganicto material formed on one or both of the substrates.

The substrates that have been subjected to the orientation treatment areso disposed that the orientation-treated surfaces or the surfaces onwhich TFTs, transparent electrodes, etc. are formed are opposed to eachother, and a liquid crystal material is interposed between the opposedsubstrates. Spacers or the like are distributed between the pair ofsubstrates to provide a constant substrate gap. Spacers having adiameter of 1-10 μm are used. The pair of substrate are fixed to eachother with an epoxy adhesive, for instance. The adhesive is applied to acircumferential portion of the substrates so as to surround the pixelregion and the peripheral driver circuit regions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1G are sectional views showing a low-temperature polysiliconprocess according to a first embodiment of the present invention;

FIGS. 2A and 2B show a general configuration of an integrated activematrix panel according to a second embodiment of the invention;

FIGS. 3A and 3B show a general configuration of an integrated activematrix panel according to a third embodiment of the invention;

FIGS. 4A-4G are sectional views showing a low-temperature polysiliconprocess according to the third embodiment of the invention;

FIGS. 5A-5F and FIGS. 6A-6D show a manufacturing process of an activematrix liquid crystal display device according to a fourth embodiment ofthe invention;

FIG. 7 is a sectional view taken along line A-A′ in FIG. 6C;

FIG. 8 is a circuit diagram showing part of an active matrix circuitaccording to the fourth embodiment of the invention;

FIGS. 9A and 9B show the shape of a wiring line according to a fifthembodiment of the invention;

FIG. 10 shows a liquid crystal display device having a planation filmaccording to a sixth embodiment of the invention;

FIGS. 11A and 11B show examples of active matrix liquid crystal displaydevices; and

FIG. 12 shows another example of an active matrix liquid crystal displaydevice.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following, there are described manufacturing methods of asubstrate of a liquid crystal display device using an active matrixcircuit according to the present invention.

Embodiment 1

Referring to FIGS. 1A-1G, a description is made of a manufacturingprocess of a monolithic active matrix circuit according to a firstembodiment of the invention. This is a low-temperature polysiliconprocess. In FIGS. 1A-1G, the left side shows a manufacturing process ofTFTs 99 of a driver circuit and the right side shows a manufacturingprocess of a TFT 100 of an active matrix circuit.

First, a silicon oxide film of 1,000-3,000 Å in thickness, i.e., anundercoat oxide film 102 is formed on a glass substrate 101 (firstinsulating substrate) by sputtering or plasma CVD in an oxygenatmosphere.

Then, an amorphous silicon film having a thickness of 300-1,500 Å,preferably 500-1,000 Å, is formed by plasma CVD or LPCVD, andcrystallized or improved in crystallinity by thermal annealing at atemperature not lower than 500° C., preferably 500-600° C. Opticalannealing (for instance, laser annealing) may be performed after thethermal annealing to further improve the crystallinity. Further, asdescribed in Japanese Patent Laid-Open No. 6-244103 and 6-244104, anelement (catalyst element) such as nickel for acceleratingcrystallization of silicon may be added in the crystallization step bythermal annealing.

Next, the silicon film is etched into island-like active layers 103 (fora P-channel TFT) and 104 (for an N-channel TFT) of TFTs 99 of a drivercircuit and an island-like active layer 105 of a TFT (pixel TFT) 100 ofa matrix circuit. A silicon oxide gate insulating film 106 of 500-2,000Å in thickness is then formed by sputtering in an oxygen atmosphere.Alternatively, it may be formed by plasma CVD. In this case, favorableresults are obtained by using material gases of dinitrogen monoxide(N₂O) or oxygen (O₂), and monosilane (SiH₄).

Thereafter, an aluminum film of 2,000-6,000 Å in thickness is formed onthe entire substrate surface by sputtering. To prevent occurrence ofhillocks in a subsequent heating process, the aluminum film may containsilicon, scandium, palladium, or the like. Gate electrodes 107-109 areformed by etching the aluminum film. (FIG. 1A)

The aluminum gate electrodes 107-109 are then anodized. As a result, thesurfaces of the gate electrodes 107-109 are formed with aluminum oxidelayers 110-112, which serve as insulating layers. (FIG. 1B)

Next, a photoresist mask 113 is so formed as to cover the active layer103 which constitutes the P-channel TFT of the TFTs 99.

Phosphorus ions are then implanted at a dose of 1×10¹² to 5×10¹³atoms/cm² through ion doping by using a doping gas of phosphine. As aresult, strong N-type regions (sources and drains) 114 and 115 areformed. (FIG. 1C)

Next, a photoresist mask 116 is so formed as to cover the active layer104 which constitutes the N-channel TFT of the TFTs 99 and the activelayer 105 which constitutes the pixel TFT. Boron ions are implanted at adose of 5×10¹⁴ to 8×10¹⁵ atoms/cm² through ion doping by using a dopinggas of dibarane (B₂H₆). As a result strong P-type regions 117 (sourceand drain) are formed. That is, the strong N-type regions (sources anddrains) 114 and 115 and the strong P-type regions (source and drain) 117are formed by the above doping. (FIG. 1D)

Thereafter, thermal annealing is performed at 450-850° C. for 0.5-3hours to repair damage by the doping, activate the doped impurities, andrestore the crystallinity of silicon. A silicon oxide film of3,000-6,000 Å in thickness as an interlayer insulating film 118 is thenformed over the en re surface through plasma CVD. Alternatively, asilicon nitride film or a multi-layer film of a silicon oxide film and asilicon nitride film may be formed. Contact holes for the sources anddrains are formed by etching the interlayer insulating film 118 throughwet etching or dry etching.

Then, an aluminum film or a titanium/aluminum multi-layer film of2,000-6,000 Å in thickness is formed through sputtering. By etching thisfilm, electrodes/wiring lines 119-121 of the TFTs 99 of the drivercircuit and electrodes/wiring lines 122 and 123 of the pixel TFT 100 areformed. (FIG. 1E) Further, a silicon nitride film 124 of 1,000-3,000 Åin thickness as a passivation film is formed through plasma etching andthen etched to form a contact hole that reaches the electrode 123 of thepixel TFT 100. Next, an ITO (indium tin oxide) film of 500-1,500 Å inthickness is formed through sputtering and then etched to form a pixelelectrode 125. Further, a 2,000-Å-thick silicon nitride film is formedthrough plasma CVD and then etched to become an interlayer film 126.(FIG. 1F)

Next, a black matrix 127 made of a resin material is formed in regionsexcluding the pixel electrodes 125, that is, formed on the TFTs 99 ofthe driver circuit and on wiring line regions including the pixel TFTs100. The black matrix 127 is formed by applying, by spin coating orprinting, a solution in which carbon black having an average particlediameter of 1,000 Å is dispersed in an acrylic resin material. Afterprebaking is performed at 100° C. for 2 min, the film is patterned by aknown photolithography technique to form a black matrix 127 on all thewiring lines and the TFTs 99 and 100 except only the pixel electrodes125. (FIG. 1G) This patterning is performed by applying strongerultraviolet light (more than 20 mW/cm²) than in ordinary patterning, sothat the patterning time is insufficient to allow reaction with oxygen.An oxygen shielding film of PVA (polyvinyl alcohol), for instance, maybe formed after the application of the black matrix. The reason for theshielding from oxygen is that the existence of oxygen cause the resinmaterial to react with it and the quality of a resulting film is therebylowered.

The development is performed by using a developing liquid in which TMAHis dissolved in water at 2.36 wt %. As a result, the 1-μm-thick blackmatrix 127 was formed on the peripheral driver circuit 99, the pixel TFT100, and the gate/source wiring lines. The aperture ratio of the pixelregion is 60%.

A liquid crystal panel is formed by bonding the thus-formed TFTsubstrate to an opposed substrate. The substrate gap is made uniformover the entire panel by interposing 5-μm-diameter spherical spacersbetween the two substrates. To bond and fix the two substrate to eachother, they are sealed with an epoxy adhesive with a pattern thatsurrounds the pixel region and the peripheral driver circuit regions.After the two substrates are cut into a given shape, a liquid crystalmaterial is injected between the two substrates.

In the liquid crystal display device, since the black matrix is made ofa resin material, the interlayer insulating film between the TFTs of thedriver circuits and the black matrix has a capacitance is negligiblysmall.

Although in this embodiment the part of the black matrix formed on thepixel TFTs is made of a resin material, it may be also made of chromium.However, where the black matrix on the driver circuits and that on thepixel TFTs are formed with different materials, the number ofmanufacturing steps is increased. It is also possible to form no blackmatrix on the pixel TFTs.

Embodiment 2

This embodiment is directed to the configuration of an integrated liquidcrystal panel which is formed according to the manufacturing method ofthe first embodiment and in which six panels are unified. FIGS. 2A and2B show a general configuration of an integrated liquid crystal panelaccording to this embodiment.

FIG. 2A is a plan view of the integrated liquid crystal panel and showsa general configuration of a substrate on which TFTs are formed. FIG. 2Bis a sectional view taken along line A-A′ in FIG. 2A. FIGS. 2A and 2Bshow a state in which the resin black matrix 127 of the first embodimentis formed in peripheral driver circuits 201, 202 and 209-211.

In the peripheral driver circuits, because of a high degree of isintegration, such defects as reduce the production yield occur at a highpossibility. According to an empirical rule in forming an integratedcircuit, the yield is lower in a peripheral portion of a substrate thanin its central portion. This is considered due to various factors suchas substrate distortion that is more remarkable in a peripheral portion,existence of dust that is higher in probability in a peripheral portion,and a mask registration error.

The reduction in yield due to such various factors becomes moreremarkable as the degree of integration of a circuit increases.Therefore, to increase the yield of the entire device, it is effectiveto form highly integrated circuits in a central portion of a substrate,if possible.

The liquid crystal panel of FIGS. 2A and 2B is characterized in that afirst set of panels 203-205 for formation of a color image (R, G and B)and a second set of panels 206-208 for formation of another color image(R′, G′ and B′) are integrated, and that peripheral driver circuits 201,202 and 209-211 are commonly used for those panels for each ofhorizontal scanning and vertical scanning.

Embodiment 3

This embodiment is directed to a case where a planation film is providedon a substrate according to the second embodiment on which TFTs areformed. That is, a planation film 428 is provided in a pixel region andregions where a black matrix is formed.

FIGS. 3A and 3B show this embodiment in which the same referencenumerals as in the second embodiment denote the same parts.

First, a substrate according to the second embodiment formed with TFTsare produced according to the manufacturing method of the firstembodiment. FIGS. 4A-4G show a specific manufacturing process.

First, a silicon oxide film of 1,000-3,000 Å in thickness, i.e., anundercoat oxide film 402 is formed on a glass substrate 401 (firstinsulating substrate) through sputtering or plasma CVD in an oxygenatmosphere.

Then, an amorphous silicon film having a thickness of 300-1,500 Å,preferably 500-1,000 Å, is formed by plasma CVD or LPCVD, andcrystallized or improved in crystallinity by thermal annealing at atemperature not lower than 500° C., preferably 500-600° C. Opticalannealing (for instance, laser annealing) may be performed after thethermal annealing to further improve the crystallinity. Further, asdescribed in Japanese Patent Laid-Open No. 6-244103 and 6-244104, anelement (catalyst element) such as nickel for acceleratingcrystallization of silicon may be added in the crystallization step bythermal annealing.

Next, the silicon film is etched into island-like active layers 403 (fora P-channel TFT) and 404 (for an N-channel TFT) of TFTs 399 of a drivercircuit and an island-like active layer 405 of a TFT (pixel TFT) 400 ofa matrix circuit. A silicon oxide gate insulating film 406 of 500-2,000Å in thickness is then formed through sputtering in an oxygenatmosphere. Alternatively, it may be formed by plasma CVD. In this case,favorable results are obtained by using material gases of dinitrogenmonoxide (N₂O) or oxygen (O₂), and monosilane (SiH₄).

Thereafter, an aluminum film of 2,000-6,000 Å in thickness is formed onthe entire substrate surface by sputtering. To prevent occurrence ofhillocks in a subsequent heating process, the aluminum film may containsilicon, scandium, palladium, or the like. Gate electrodes 407-409 wereformed by etching the aluminum film. (FIG. 4A)

The aluminum gate electrodes 407-409 are then anodized. As a result, thesurfaces of the gate electrodes 407-409 are formed with aluminum oxidelayers 410-412, which serve as insulating layers. (FIG. 4B)

Next, a photoresist mask 413 is so formed as to cover the active layer403 which constitutes the P-channel TFT of the TFTs 399. Phosphorus ionsare then implanted at a dose of 1×10₁₂ to 5×10¹³ atoms/cm² through iondoping by using a doping gas of phosphine. As a result, strong N-typeregions (sources and drains) 414 and 415 are formed. (FIG. 4C)

Next, a photoresist mask 416 is so formed as to cover the active layer404 which constitutes the N-channel TFT of the TFTs 399 and the activelayer 405 which constitutes the pixel TFT. Boron ions are implanted at adose of 5×10¹⁴ to 8×10¹⁵ atoms/cm² through ion doping by using a dopinggas of dibarane (B₂H₆)!As a result strong P-type regions 417 (source anddrain) are formed. That is, the strong N-type regions (sources anddrains) 414 and 415 and the strong P-type regions (source and drain) 417are formed through the above doping. (FIG. 4D)

Thereafter, thermal annealing is performed at 450-850° C. for 0.5-3hours to repair damage by the doping, activate the doped impurities, andrestore the crystallinity of silicon. A silicon oxide film of3,000-6,000 Å in thickness as an interlayer insulating film 418 is thenformed over the entire surface through plasma CVD. Alternatively, asilicon nitride film or a multi-layer film of a silicon oxide film and asilicon nitride film may be formed. Contact holes for the sources anddrains are formed by etching the interlayer insulating film 418 throughwet etching or dry etching.

Then, an aluminum film or a titanium/aluminum multi-layer film of2,000-6,000 Å in thickness is formed through sputtering. By is etchingthis film, electrodes/wiring lines 419-421 of the TFTs 399 of the drivercircuit and electrodes/wiring lines 422 and 423 of the pixel TFT 400 areformed. (FIG. 4E) Further, a silicon nitride film 424 of 1,000-3,000 Åin thickness as a passivation film is formed through plasma etching andthen etched to form a contact hole that reaches the electrode 423 of thepixel TFT 400. Next, an ITO (indium tin oxide) film of 500-1,500 Å inthickness is formed through sputtering and then etched to form a pixelelectrode 425. Further, a 2,000-Å-thick silicon nitride film is formedthrough plasma CVD and then etched to become an interlayer film 426.(FIG. 4F)

Next, a black matrix 427 made of a resin material is formed in regionsexcept the pixel electrodes 425, that is, formed on the TFTs 399 of thedriver circuit and on wiring line regions including the pixel TFTs 400.The black matrix 427 is formed by applying, through spin coating orprinting, a solution in which carbon black having an average particlediameter of 1,000 Å is dispersed in an acrylic resin material. Afterpre-baking is performed at 100° C. for 2 min, the film is patterned by aknown photolithography technique to form a black matrix 427 on all thewiring lines and the TFTs 399 and 400 except only the pixel electrodes425. This patterning is performed by applying stronger ultraviolet light(more than 20 mW/cm²) than in ordinary patterning so that the patterningtime is insufficient to allow reaction with oxygen. Also an oxygenshielding film of PVA (polyvinyl alcohol), for instance, may be formedafter the application of the black matrix. The reason for the shieldingfrom oxygen is that the existence of oxygen may cause the resin materialto react with it and the quality of a resulting film is thereby lowered.

The development is performed by using a developing liquid in which TMAHis dissolved in water at 2.36 wt %. As a result, the 1-μm-thick blackmatrix 427 is formed on the peripheral driver circuit 399, the pixel TFT400, and the gate/source wiring lines. The aperture ratio of the pixelregion is 60%.

Next, the surface is planarized by applying a resin liquid mainly madeof an acrylic resin to the black matrix 427 and the pixel region with aspin coater. The resin liquid is completely set into the planation film428 by a heat treatment of 170° C. and 3 hours. The planation film 428has a thickness of 1-2 μm. (FIG. 4G)

Examples of the material of the planation film 428 other than theacrylic resin as mentioned above include an aminosilane modified epoxyresin and a polyimide resin.

Where a planation film is formed as in this embodiment, a flatorientation film can be formed in the pixel region, resulting inimproved orientation of a liquid crystal.

A liquid crystal panel is formed by bonding the thus-formed TFTsubstrate to an opposed substrate. The substrate gap is made uniformover the entire panel by interposing 5-μm-diameter spherical spacersbetween the two substrates. To bond and fix the two substrates to eachother, they are sealed with an epoxy adhesive with a pattern thatsurrounds the pixel region and the peripheral driver circuit regions.After the two substrates are cut into a given shape, a liquid crystalmaterial is injected between the two substrates.

In the liquid crystal display device, since the black matrix is made ofa resin material, the interlayer insulating film between the TFTs of thedriver circuits and the black matrix has a capacitance is negligiblysmall.

Although in this embodiment the part of the black matrix formed on thepixel TFTs is made of a resin material, it may be made of chromium.However, where the black matrix on the driver circuits and that on thepixel TFTs are formed with different materials, the number ofmanufacturing steps is increased. It is also possible to form no blackmatrix on the pixel TFTs.

Embodiment 4

This embodiment is directed to a case where a special feature is addedto the TFT manufacturing processes of the first and third embodiments.This embodiment relates to a manufacturing method that has a feature forpreventing semiconductor devices being manufactured from being broken bya high voltage pulse that is imparted from plasma in performing plasmaCVD or sputtering.

FIGS. 5A-5F and 6A-6D show a general manufacturing process according tothis embodiment. First, a step of FIG. 5A is described. A 3,000-Å-thicksilicon oxide film as an undercoat film (not shown) is formed on a glasssubstrate 501 through plasma CVD or sputtering. Alternatively, thesubstrate 501 may be a quartz substrate.

Next, a 500-Å-thick amorphous silicon film (not shown) as a startingfilm of an active layer 502 is formed through plasma CVD or low-pressurethermal CVD. A crystalline silicon film (not shown) is obtained bycrystallizing the amorphous silicon film by heating and/or laser lightapplication. Alternatively, a crystalline silicon film may be formeddirectly through low-pressure thermal CVD or plasma CVD.

The crystalline silicon film thus obtained is patterned into an activelayer 502 (see FIG. 5A) for a thin-film transistor by using a firstmask.

Next, a 1,000-Å-thick silicon oxide film 500 to serve as a galeinsulating film is formed through plasma CVD.

Further, an aluminum film (not shown) for first-layer wiring lines506-508 (see FIG. 5A) is formed through sputtering or electron beamevaporation.

To suppress occurrence of hillocks and whiskers in subsequent steps, itis effective that the aluminum film contain Sc, Y, or at least one ofelement selected from the lanthanoids and actinoids. In this embodiment,Sc is included in the aluminum film at 0.1 wt %.

Hillocks and whiskers are needle or prickle-like protrusions that may beformed on the surface of an aluminum film when the film is heated tomore than 300° C. or it is illuminated with laser light.

Further, a very thin, dense anodic oxide film (not shown) is formed onthe surface of the aluminum film (not shown) to improve the adhesivenessof resist masks 503-505 to be formed on the aluminum film.

The anodization is performed by using an electrolyte that an ethyleneglycol solution containing 3%-tartaric acid neutralized with aqueousammonia. That is, the anodization is performed in the electrolyte withthe aluminum film and a platinum plate used as the anode and cathode,respectively. The thickness of a resulting dense anodic oxide film isset at 150 Å. The thickness of a dense anodic oxide film can generallybe controlled by the application voltage.

Resist masks 503-505 are then formed on the aluminum film. By virtue ofthe dense anodic oxide film (not shown) formed on the aluminum film,superior adhesiveness are attained between the resist masks 503-505 andthe aluminum film. A second mask is used in forming the resist masks503-505.

Next, the aluminum film is patterned by using the resist film masks503-505 into a gate electrode 506 and a gate line (not shown) extendingtherefrom, a part 507 of a shorting line for connecting the gate lineand a source line later, and a part 508 of a wiring line for supplyingcurrent in later anodization of the gate electrode 506. Thus, a state ofFIG. 5A is obtained.

Next, with the resist masks 503 and 505 left as they are, porous anodicoxide films 509-511 are formed as shown in FIG. 5B by using a 3% aqueoussolution of oxalic acid. Specifically, the anodization is performed inthe above aqueous solution by electrifying between the first-layerwiring lines 506-508 (anode) formed in the FIG. 5A step and a platinumplate (cathode).

Because of the existence of the resist masks 503-505 on the respectivealuminum patterns 506-508, the electrolyte does not contact with the topsurfaces of the aluminum patterns 506-508 and hence the anodizationproceeds only on the side faces of the respective patterns 506-508.

This anodization is performed by electrifying through the current supplyline for anodization (reference numeral 508 denotes its part) to preventa case that voltage drops otherwise cause resulting anodic oxide filmsto have different thicknesses at opposite ends of the active matrixregion. In particular, the use of the current supply lines is necessaryto produce a large-area liquid crystal panel.

The growth distance of the porous anodic oxide films 509-511 can becontrolled by the anodization time, and can be selected from anapproximate range of 3,000-10,000 Å. In this embodiment, the thickness(growth distance) of the porous anodic oxide films 509-511 is set at5,000 Å. The dimension of low-concentration impurity regions (formedlater) can generally be determined by the growth distance of the porousanodic oxide film 509.

As described later in detail, the porous anodic oxide regions 509-511have the following important roles:

formation of low-concentration impurity regions (generally called LDDregions); and

suppressing the occurrence of defects at crossing points of thefirst-layer and second-layer wiring lines.

After the formation of the porous anodic oxide films 509-511 (see FIG.5B), the resist films 503-505 (not shown in FIG. 5B) are removed andthen the 150-Å-thick, dense anodic oxide films (not shown) are alsoremoved.

Thereafter, dense anodic oxide films 512-514 are formed, which are veryeffective in suppressing the occurrence of hillocks and whiskers.

The dense anodic oxide films 512-514 are formed by using an electrolytethat an ethylene glycol solution containing 3%-tartaric acid neutralizedwith aqueous ammonia,.

In this step, since the electrolyte enters the porous anodic oxide films509-511, the dense anodic oxide films 512-514 are formed on the surfacesof the residual aluminum electrodes and wiring lines 506-508.

Also in this anodization step, anodization current is supplied throughthe current supply line for anodization (reference numeral 508 denotesits part), to uniformize the thickness of the resulting anodic oxidefilms over the entire active matrix region.

The thickness of the dense anodic oxide films 512-514 was set at 800 Å.If the thickness of the dense anodic oxide films 512-514 were madethicker (for instance, more than 2,000 Å), offset regions later formedin the active layer could also be made thicker as much. However, to thisend, the application voltage needs to be increased to more than 200 V,which is not preferable in terms of reproducibility and safety ofoperation. Therefore, in this embodiment, to obtain the effects ofsuppressing the occurrence of hillocks and whiskers and increasing thebreakdown voltage, the thickness of the dense anodic oxide films 512-514is set at 800 Å.

As a result of the above step, the gate electrode and gate line 506 isformed as shown in FIG. 5B, whose dimension is smaller than thecorresponding dimension in FIG. 5A by the anodization.

The dense anodic oxide films 513 and 514 and the porous anodic oxidefilms 510 and 511 are also formed around the part 507 of the shortingline for connecting the gate line 506 and the source line and the part508 of the current supply line for anodization of the gate electrode506.

Thus, a state of FIG. 5B is obtained. Thereafter, the exposed portionsof the silicon oxide film 503 are removed to form low-concentrationimpurity regions in the active layer 502 of the thin-film transistor.Thus, a state of FIG. 5C is obtained, in which silicon oxide films515-517 remained.

Next, the porous anodic oxide films 509-511 are removed (see FIG. 5D).They can be removed selectively by using a mixed acid of phosphoricacid, acetic acid, and nitric acid.

In this state, impurity ions are implanted to form source and drainregions of the thin-film transistor. Specifically, phosphoric ions areimplanted to form an N-channel thin-film transistor. To form a P-channelthin-film transistor rather than an N-channel one, boronic ions may beimplanted.

In this step, a source region 518 and a drain region 522 as well aslow-concentration impurity regions 519 and 521 are formed in aself-aligned manner. The low-concentration regions 521 that is formedbetween a channel forming region 520 and the drain region 522 is usuallycalled a lightly doped drain. (FIG. 5D)

The low-concentration impurity regions 519 and 521 are very effective inproducing a thin-film transistor having a small off-currentcharacteristic. In particular, obtaining a small off-currentcharacteristic by forming low-concentration impurity regions isadvantageous in a thin-film transistor provided in each pixel of anactive matrix region because it is required to have such acharacteristic.

After the implantation of impurity ions, laser light is applied toactivate the implanted impurity ions and to anneal the regions which aredamaged by the ion implantation. In this operation, the previouslyformed dense anodic oxide films 512-514 prevent hillocks and whiskersfrom occurring in the gate electrode 506 and the wiring lines 507 and508.

Next, a 4,000-Å-thick silicon oxide film to serve as a first interlayerinsulating film 523 is formed through plasma CVD using a TEOS materialgas.

Alternatively, the interlayer insulating film may be a silicon nitridefilm or a silicon oxynitride film. In the case of forming a siliconnitride film, plasma CVD may be used with a material gas of ammonia. Inthe case of forming a silicon oxynitride film, plasma CVD may be usedwith material gases of TEOS and N₂O.

As a further alternative, the first interlayer insulating film 523 maybe a laminate film of a plurality of films selected from a silicon oxidefilm, a silicon nitride film, and a silicon oxynitride film.

Thereafter, contact holes are formed through the first interlayerinsulating film 523 by using a third mask, to obtain a state of FIG. 5E.

Second-layer electrodes and wiring lines (usually called second-layerwiring lines) are then formed each of which is a three-layer filmconsisting of a titanium film, an aluminum film, and a titanium film.The thickness of the titanium films may be less than several hundredangstrom because they are merely used to obtain good contact. A fourthmask is used in this step.

Although each of the second-layer wiring layers may be a single-layeraluminum film, the above-mentioned three-layer film is used in thisembodiment to obtain good contact with other electrodes and wiringlines.

It is necessary to use different etchants for the etching of thetitanium films and the aluminum films. In this embodiment, ammoniumperoxide is used for the etching of the titanium films and an aluminummixed acid was used for the etching of the aluminum films.

Thus, a state of FIG. 5F is obtained. In FIG. 5F, reference numeral 524denotes a source electrode and wiring line and 525 denotes a gateelectrode. The gate electrode 525 is so formed as to extend from thegate line 506, though it is not shown in FIG. 5F. The wiring lines andelectrodes 524 and 525 are second-layer wiring lines.

The source line 524 and the gate electrode (gate line) 525, which aresecond-layer wiring lines, are connected to each other via a shortingline. This structure eliminates a voltage difference between the sourceline 524 and the gate electrode 525.

The source line 524 is so formed as to cross, i.e., overpass the currentsupply line 508 for anodization with the first interlayer insulatingfilm 523 interposed in between.

FIG. 5F also shows dummy electrodes (called “electrodes” for convenienceof description) 526-528 which do not serve as electrodes or wiring linesbut are used in a later dividing step. That is, they play their roles individing the wiring line 507 and 508 in the final step.

Next, a 4,000-Å-thick silicon oxide film as a second interlayerinsulating film 529 is formed. Alternatively, the second interlayerinsulating film 529 may be a silicon nitride film, a silicon oxynitridefilm, or a laminate film consisting of those insulating films and asilicon oxide film.

During the formation of the second interlayer insulating film 529, thesource line 524 and the gate electrode 525 are short-circuited with eachother via the shorting line 507. There, it can be avoided that plasmacauses a voltage difference between the source line 524 and the gateelectrode 525 and the voltage difference in turn electrostaticallybreaks down the gate insulating film (silicon oxide film) 515.

Next, contact holes 530-533 are formed by using a fifth mask, to obtaina state of FIG. 6A. Reference numeral 530 denotes a contact hole for thedrain region 522, an opening 531 that is necessary to divide the wiringline 507, and openings 532 and 533 that are necessary to divide thewiring line 508.

In this step, the surface of an end portion 534 of the source electrodeand wiring line 524 is exposed, which portion later served as anexternal lead-out terminal. Actually, the source line 524 is connectedto a peripheral driver circuit for driving the active matrix circuit andthe terminal 534 is an external terminal of this peripheral drivercircuit. However, to avoid complexity, the peripheral driver circuit isnot shown in FIGS. 6A-6D.

Next, an ITO electrode 535 to constitute pixel electrodes is formedthrough sputtering, to obtain a state of FIG. 6B. The ITO electrode 535is then patterned into a pixel electrode 536 by using a sixth mask.

In forming the pixel electrode 536, after the removal of unnecessaryportions of the ITO electrode 535, the etching is continued to formholes through the electrodes (dummy electrodes; second-layer wiringlines) 526-528 and the first-layer wiring lines 507 and 508.

That is, the openings 531-533 are extended through the second-layer andfirst-layer wiring lines, whereby the wiring lines 507 and 508 aredivided.

In the above etching, since each of the second wiring lines is alaminate films of a titanium film and an aluminum film, differentetchants need to be used for the respective films.

Thus, a state of FIG. 6C is obtained. Since the above step is performedat the same time as the pixel electrode 536 is formed by patterning,there is no need of using a new mask.

The reason why the first-layer and second-layer wiring lines can beremoved at the same time is that only the metal materials can be removedselectively while the insulating films of silicon oxide films etc. areleft.

In the above step, a part of the ITO film 537 was left on the surface ofthe lead-out electrode 534 of the liquid crystal panel extending fromthe source line 524. This ITO film serves as a buffer layer forpreventing corrosion and mutual diffusion between the lead out terminal534 and a metal wiring line or a conductive pad that is to contact withthe lead-out terminal 534.

For the following reason, it is important that the current supply line508 for anodization be divided at the portions 532 and 533. In asubsequent liquid crystal panel assembling process, a rubbing resin filmis so formed as to cover the second interlayer insulating film and thenrubbing is performed to orient a liquid crystal. In this operation,since the wiring line 508 is electrically in a floating state, there canbe prevented an event that an undesired voltage difference occursbetween the source line 524 and the wiring line 508.

As shown in FIG. 6C, the wiring lines 507 and 508 are divided at onelocation and two locations, respectively. The dividing positions may beset as desired.

FIG. 7 is a sectional view taken along line A-A′ in FIG. 6C. As shown inFIG. 7, the source line 524 overpasses the current supply wiring line508 for anodization to provide a crossing. It is noted that a portion701 of the wiring line 508 has a step-like shape because of the previousformation of the porous anodic oxide film.

Therefore, a portion 702 of the first interlayer insulating film 523 isgiven a gently sloped surface, which prevents the source line 524 frombeing cut due to the existence of a step.

In the state of FIG. 6C, a black matrix 538 made of a resin material wasformed in regions except the pixel electrodes, that is, formed on theTFTs of the driver circuit and on wiring line regions including thepixel TFTs. (FIG. 6D) The black matrix 538 is formed by applying,through spin coating or printing, a solution in which carbon blackhaving an average particle diameter of 1,000 Å is dispersed in anacrylic resin material. After pre-baking is performed at 100° C. for 2min, the film is patterned by a known photolithography technique to forma black matrix 538 on all the wiring lines and the TFTs except only thepixel electrodes. This patterning is performed by applying strongerultraviolet light (more than 20 mW/cm²) than in ordinary patterning sothat the patterning time is insufficient to allow reaction with oxygen.also an oxygen shielding film of PVA (polyvinyl alcohol), for instance,may be formed after the application of the black matrix. The reason forthe shielding from oxygen is that the existence of oxygen may cause theresin material to react with it and the quality of a resulting film isthereby lowered.

The development is performed by using a developing liquid in which TMAHis dissolved in water at 2.36 wt %. As a result, the 1-μm-thick blackmatrix 538 is formed on the peripheral driver circuit, the pixel TFT,and the gate/source wiring lines. The aperture ratio of the pixel regionis 60%.

A liquid crystal panel is formed by bonding the thus-formed TFTsubstrate to an opposed substrate. The substrate gap is made uniformover the entire panel by interposing 5-μm-diameter spherical spacersbetween the two substrates. To bond and fix the two substrate to eachother, they are sealed with an epoxy adhesive with a pattern thatsurrounds the pixel region and the peripheral driver circuit regions.After the two substrates are cut into a given shape, a liquid crystalmaterial is injected between the two substrates.

In the liquid crystal display device thus formed, since the black matrix538 is made of a resin material, the interlayer insulating film betweenthe TFTs of the driver circuits and the black matrix 538 has acapacitance is negligibly small.

In forming the black matrix 538, the openings 531-533 are filled withthe material of the black matrix 538. Since this material is a resinmaterial, filling the openings 531-533 with the material of the blackmatrix 538 is effective in providing high reliability.

FIG. 8 shows part of an active matrix circuit of an active matrix liquidcrystal panel which circuit is employed in this embodiment. FIG. 8 doesnot include a peripheral driver circuits for inputting drive signals tothe source line 524 and the gate line 525.

In the configuration of FIG. 8, the gate line 525 and the source line524 are short-circuited by the shorting line 507. The shorting line 507is divided by the opening 531 in the step of FIG. 6C.

In the step of FIG. 6C, the current supply line 508 for anodization isdivided by the openings 532 and 533. The source line 524 overpasses theportion of the current supply line 508 extending between the dividingportions with the interlayer insulating film 523 interposed in between.

Embodiment 5

This embodiment is directed to the shape of a first-layer wiring linethat is divided by openings such as the openings 532 and 533 shown inFIG. 6C. For example, the wiring line 508 becomes unnecessary once theanodization is finished. However, there is a concern that a pulsecurrent caused by local abnormal discharge may flow through the longwiring line 508 during the formation of the first interlayer insulatingline 523 or the second interlayer insulating line 529.

In forming the first interlayer insulating line 523 or the secondinterlayer insulating line 529, the wiring line 508 is connected to eachgate electrode. Therefore, if a pulse current flows through the wiringline 508, a pulse voltage is applied to each gate electrode.

To solve this problem, in this embodiment, the wiring line 508 has abracket shape at the dividing portions as shown in FIG. 9A, so that apulse current is caused to disappear or attenuate at those portions.FIGS. 9A and 9B show states before and after the dividing.

The bracket-shaped portions are removed by the openings 532 and 533shown in FIG. 6C. Although this configuration requires the openings 532and 533 to be increased in size, it can be said that the increase in thesize of the openings 532 and 533 is, rather, preferable if takingaccount of the viscosity etc. of the black matrix material that isfinally filled up.

Embodiment 6

This embodiment is directed to a case where a planation film 539 isformed after the TFT manufacturing process of the fourth embodiment inthe pixel region and the region where black matrix is formed.

After the black matrix is formed by the same process as in the fourthembodiment, the planation film 539 is formed by the same planation filmforming method as in the third embodiment. An example is shown in FIG.10.

According to the invention, by employing, in a liquid crystal displaydevice, the structure in which a black matrix is formed on a peripheraldriver circuit, it can be prevented that a capacitance occurs in aninterlayer insulating film formed between TFTs of the driver circuit andthe black matrix. As a result, the delay time of the driver circuit canbe reduced, which makes it possible to produce high-resolution images.

By utilizing the invention, the whole structure of a liquid crystaldisplay device can be made as simple as possible and its manufacturingcost can be reduced while high-quality images can be produced.

Further, by properly arranging peripheral driver circuits, reduction inproduction yield can be avoided even if the degree of integration of aliquid crystal panel is increased.

1. A display device comprising: a first substrate; a second substrateopposed to said first substrate; a thin film transistor having an activelayer comprising amorphous semiconductor comprising silicon providedover said first substrate; a color filter provided over said secondsubstrate; a resin black matrix provided over said second substrate andcomprising a resin and a a carbon black; and a planation film providedover said second substrate, wherein said carbon black has an averagediameter greater than zero and up to about 0.1 μm.
 2. A display devicecomprising: a first substrate; a second substrate opposed to said firstsubstrate; a thin film transistor having an active layer comprisingamorphous semiconductor comprising silicon provided over said firstsubstrate; a color filter provided over said second substrate; and aresin black matrix provided over said second substrate and comprising aresin and a a carbon black, wherein said carbon black has an averagediameter greater than zero and up to about 0.1 μm.
 3. The device ofclaim 2 further comprising a liquid crystal provided between said firstsubstrate and said second substrate, said liquid crystal being selectedfrom the group consisting of a nematic liquid crystal, a cholestericliquid crystal, a smectic liquid crystal, and a dispersive liquidcrystal in which one of said nematic liquid crystal, said cholestericliquid crystal and said smectic liquid crystal is dispersed in atransparent resin material.
 4. The device of claim 2 wherein said resincomprises an acrylic resin.
 5. The device of claim 1 further comprisinga liquid crystal provided between said first substrate and said secondsubstrate, said liquid crystal being selected from the group consistingof a nematic liquid crystal, a cholesteric liquid crystal, a smecticliquid crystal, and a dispersive liquid crystal in which one of saidnematic liquid crystal, said cholesteric liquid crystal and said smecticliquid crystal is dispersed in a transparent resin material.
 6. Thedevice of claim 1 wherein said resin comprises an acrylic resin.
 7. Adisplay device comprising: a first substrate; a second substrate opposedto said first substrate; a thin film transistor having an active layercomprising amorphous semiconductor comprising silicon provided over saidfirst substrate; a resin black matrix provided over said secondsubstrate and comprising a resin and a carbon black; and a planationfilm provided over said second substrate, wherein said carbon black hasan average diameter greater than zero and up to about 0.1 μm.
 8. Thedevice of claim 7 further comprising a liquid crystal provided betweensaid first substrate and said second substrate, said liquid crystalbeing selected from the group consisting of a nematic liquid crystal, acholesteric liquid crystal, a smectic liquid crystal, and a dispersiveliquid crystal in which one of said nematic liquid crystal, saidcholesteric liquid crystal and said smectic liquid crystal is dispersedin a transparent resin material.
 9. The device of claim 7 wherein saidresin comprises an acrylic resin.
 10. A display device comprising: afirst substrate; a second substrate opposed to said first substrate; athin film transistor provided over said first substrate and comprising asource region, a drain region, a channel forming region provided betweensaid source region and said drain region, at least said channel formingregion comprising an amorphous semiconductor comprising silicon; a colorfilter provided over said second substrate; a resin black matrixprovided over said second substrate and comprising a resin and a carbonblack; and a planation film provided over said second substrate, whereinsaid thin film transistor further comprises a low-concentration impurityregion provided between said channel forming region and at least one ofsaid source region and said drain region, and wherein said carbon blackhas an average diameter greater than zero and up to about 0.1 μm. 11.The device of claim 10 further comprising a liquid crystal providedbetween said first substrate and said second substrate, said liquidcrystal being selected from the group consisting of a nematic liquidcrystal, a cholesteric liquid crystal, a smectic liquid crystal, and adispersive liquid crystal in which one of said nematic liquid crystal,said cholesteric liquid crystal and said smectic liquid crystal isdispersed in a transparent resin material.
 12. The device of claim 11wherein said resin comprises an acrylic resin.
 13. The device of claim10 wherein said resin comprises an acrylic resin.
 14. A displaycomprising: a first substrate: a second substrate opposed to said firstsubstrate; a thin film transistor provided over said first substrate andcomprising a source region, a drain region, a channel forming regionprovided between said source region and said drain region, at least saidchannel forming region comprising an amorphous semiconductor comprisingsilicon; a color filter provided over said second substrate; and a resinblack matrix provided over said second substrate and comprising a resinand a carbon black, wherein said thin film transistor further comprisesa lowconcentration impurity region provided between said channel formingregion and at least one of said source region and said drain region, andwherein said carbon black has an average diameter greater than zero andup to about 0.1 μm.
 15. A display device comprising: a first substrate:a second substrate opposed to said first substrate; a thin filmtransistor provided over said first substrate and comprising a sourceregion, a drain region, a channel forming region provided between saidsource region and said drain region, at least said channel formingregion comprising an amorphous semiconductor comprising silicon; a resinblack matrix provided over said second substrate and comprising a resinand a carbon black; and a planation film provided over said secondsubstrate, wherein said thin film transistor further comprises alow-concentration impurity region provided between said channel formingregion and at least one of said source region and said drain region, andwherein said carbon black has an average diameter greater than zero andup to about 0.1 μm.
 16. The device of claim 14 further comprising aliquid crystal provided between said first substrate and said secondsubstrate, said liquid crystal being selected from the group consistingof a nematic liquid crystal, a cholesteric liquid crystal, a smecticliquid crystal, and a dispersive liquid crystal in which one of saidnematic liquid crystal, said cholesteric liquid crystal and said smecticliquid crystal is dispersed in a transparent resin material.
 17. Thedevice of claim 16 wherein said resin comprises an acrylic resin. 18.The device of claim 15 further comprising a liquid crystal providedbetween said first substrate and said second substrate, said liquidcrystal being selected from the group consisting of a nematic liquidcrystal, a cholesteric liquid crystal, a smectic liquid crystal, and adispersive liquid crystal in which one of said nematic liquid crystal,said cholesteric liquid crystal and said smectic liquid crystal isdispersed in a transparent resin material.
 19. The device of claim 18wherein said resin comprises an acrylic resin.
 20. The device of claim15 wherein said resin comprises an acrylic resin.